Grinder.



F. H. HALSTEAD.

GRINDER.

APPLICATION FILED MAR. 7. 19|?.

Patented Apr. 8,1919. 2 SHEETS-SHEET! i lavez-daan FfdencsHezryHaZs e.

^ F'. H. HALSTEAD.

GRINDER.

APPLICATION FILED MAR. 7| 1911.

` Patented 8,1919.

2 SHEE HEET 2.

. STATES PATENT EREDERICKRHALSTEAD, or WORCESTER, MASSACHUSETTS, ASSIGNOR To RIvETT LATHE AND GRINDER COMPANY, OE EANEUIL, MASSACHUSETTS, A CORPORATION v 0F MASSACHUSETTS.

GRINDER.

T o all whom it may Concern:

`Be it known that I, FREDERICK H. HAL- s'r-EAD, -a citizen ofthe United States, and a resident of Worcester, county ofv Worcester, and State of Massachusetts, have invented an Improvement in Grinders, of which the `,following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

This invention pertains to improvements in grinders and, more particularly, though not exclusively, to improvements in mechanisms for relatively feeding together the grinding wheel and the work and mechanisms for separating the work and tool for inspection and gaging ofthe work, o r other purposes.

- In the illustrative embodiment of a preferred construction of my invention shown in the drawings, and herein specifically described, I have shown a grinder adapted for the grinding of ball races, and resembllng somewhat the ,oscillatinga grinder shown,

in my copending application, Serial No. 130,062, filed November 7, 1916.

In grinding` mechanisms, -it is the best practice, where possible to actuate the feeding movement at the end of a relative traverse of the work and tool, and preferably Whenthe work andy tool are out of Contact with each other. In grinding mechanisms providing for automatic relative traverse of work and tool, andautomatic feeding movement, this has heretofore necessitated separate adjustment ofthe periods of reversal of relative traverse and of the periods at which feeding movement is actuated. It is among the purposes of the present invention to provide reversing mechanism vand automatic feeding mechanism which are automatically, relatively timed so that av change in the position or period of reversal automaticall correspondingly changes the time of fee ing movement, thus. rendering unnecessary separate adjustment of the timing mechanism forytiming the reversal of relative traverse of work and tool, and

' of the timing mechanism for timing the actuation ofthe feeding movement.

Another object of thev present invention isV to provide an automatic feeding mechanism for automatically and intermittently relatively feeding together the work and tool in i Specification of Letters Patent.

Application led March 7, 1917. A Serial No. 153,192.

Patented Apr. y8, 1919.

Another object of the invention isto pro-l vide an improved construction for relatively separating the work ,and tool in a direction transverse to `the feeding movement without disturbing the feed slide or its auto-.

matic connections. v

Other objects and advantages of the invention will appear in the following descriptive matter.

In the drawings which show an illustrative embodiment of one form lof my invenn tion, i Y

Figure 1 is a side elevation, partially broken away, o f an illustrative grinding machine embodying a preferred form and ap'- plicatin of my invention.

` Fig. 2 'is a partial, vertical section, partly in elevation on the line 2-2-of Fig. 1, and

shows a detail of a portion'of the preferred feed mechanism selected to illustrate one phase of my invention.-

Fig. 3 is a vertical section, partly in elevation on the line 3 3 of Fig. 2.

Fig. 4 is a top plan View of the lparts l shown in Figs. 2 and'3.

v Fig. 5 is a plan of a detail of the reversing and feed actuating mechanisms shown in Fig. 1, and will be full-y described hereinafter.

Fig. 1 of the drawings shows a ball race grinder having a chuck 9, holding the work 10, and mounted on the work spindle 11, rotated in bearings 12 by a' belt (not shown) on the pulley 13.

The work'spindle bearings 12 and parts carried thereby are shown mounted on an oscillatory support .14, carried by a pivotal shaft 15 which is preferably oscillated by 'alternate engagement yof worms 16-17 with opposite'sidesfofthe worm gear 18, 'as best shown in Fig. 5.y They worms 16-17 are preferably carried by theshiftable cage 19, preferably actuated by mechanism which is fully described in my copendn application above mentioned. The grin ing wheel.

20 is carried by, a rotatable tool spindle 21 running in a bearing 22, which as shown can be fed transversely of the machine, to feed the tool into the work. The before described parts are all similar to those shown inl my copending application and require no detailed description. They constitute one form of grinding machine wherein the work and tool are relatively traversed and reversed by alternately engaged, oppositelyeffective driving elements and wherem relative feeding movement is provided. n

Referring to those features of my invention which differ from my copending application, I have shown the cross feed slide 23, carrying the work spindle bearing 22 and associated parts. The longitudinal slide 24 is preferably as shown, carried by the transverse feed slide. Feeding movement is preferably imparted to the parts carried by the feed slide through a screw shaft 25, which may be of the usual construction shown in my copending application, and preferably carrying a gear 26, driven by a pinion 27 on the ratchet shaft 28 which carries the ratchet 29. Step by step rotation is preferably imparted to the ratchet 29 by a pawl 30, carried by the reciprocatory rod 31 to which, asbest shown in Fig. 3, reciprocatory movement is imparted in one direction by a cam 32, and preferably yieldingly actuated in the'opposite direction as by the spring 33. The cam 32l is preferably moved by shifting of the reversing mechanism, and to this end I have shown it carried by an arm 34, projecting from the shifting Worm cage 19 (Fig. 5). Thus, whenever the cage 19 is shifted, preferably by mechanism shown in my copending application, the arm 34 will pass under the rod 31, pushing the latter up- Wardly and imparting movement to the pawl 30. If desired, the pawl 30 may be ren versible as shown, so that feeding movement may be imparted by said pawl and coperate with a double ratchet, as shown in my copending application, thereby imparting feeding movement in either direction to the parts carried by the feed slide, depending on Whether the pawl turns its cooperating ratchet on its upward or downward stroke. Forv the purposes of this application it is immaterial whether the shifting, reversing mechanism impart ratchet turning movement to the awl or whether it compress the spring whic imparts ratchet turning movement to the pawl. s

To regulate the amount of feed, I preferably provide means for manually varying the effective throw of the cam 32, and to ythis end I have shown the thumb nut 35,

referably knurled on the outside and having a female thread on the inside, engaging a male thread on a sleeve 36, which is preferably held non-'rotatably relative to the rod 31 by a pin 37 passing through a slot 38 in the casing 39. Rotation of the nut 35 lto this end I preferably provide anratchet 40 forming a part of the thumb nut and engaged by a pawl 41, preferably actuated by the reversing mechanism and carried by the arm 34, and pressed by a spring 45 against the ratchet 40, which it is adapted to turn in one direction only-viz., the direction which will impart feed decreasing movement to the rod 31. Thus the feed is progressively decreased until the rod 31 is elevated above the cam 32, at which point the feed will stop though the'machine may continue to run, thereby reciprocating the cam 32. To prevent jamming of the mechanism actuatedby the pawl'41, in case the machine is 'left running for too long a period, I proportion the threads on the nut 35 and sleeve 3,6, so that they will run out at the point where the rod 31 ceases to be engaged by the cam 32.

Any suitable means may be provided for discontinuing or throwing out of gear the automatic feed reducing mechanism but I prefer to provide as shown means for withholding the paWl 41 from engagement with the ratchet 40, typified by the pin 47 in the slot 48 and adapted to be caught in a lockingxportion 49 of the slot 48."

he longitudinal slide 24, carried by the cross slide 23 may coperate with anysuitable positioning means, such as the usual latches and stops for accurately determining the position of the tool during the grinding operation.

Any of the usual lever mechanisms may be provided to facilitate the movement of the tool carrying head on the longitudinal slide. -By locating the feed slide below the longitudinal slide I am enabledtogreatly increase the bearing surface of the feed slide, which .is necessarily free during the grinding operation while the longitudinal slide is preferably locked. I am also enabled to leave all parts of the cross feed mechanismstationary while the tool is Withdrawn from the work.

The operation -of the specific embodiment of my invention, illustrated inthe drawings, is as follows:

The tappets carried by the oscillatory support 14 (identical with those shown in my copending application) are set to engage the reversing pin 50 at the desired points of reversal, but preferably when the Work 10 and tool 20 are out of contact. 'The shifting of the reversing'pin through mechanism like that shown and described in my copending application shifts the Worm carrying cage 19 alternately fr'om one side to the other at the timelwhen reversalis to take place. The cam 32 being carried by the arm 34 necessarily is moved at the same time, thereby imparting feeding movement through the rod 31, pawl 30, ratchet 29., pinion 27 and gear 26 to the screw shaft 25 which effects the cross feed of the tool into the work. Then the automatic feed reducing pawl 41 is in position to engage the ratchet 40 it imparts, at every movement of the arm 34 in one direction, a partial rotation to the nut35, thereby progressively reducing the extent to which the rod 31 is permitted to engage the cam 32, and therefore gradually reducing the feeding movement.

Thile I have shown in the drawings and have described for illustrative purposes a preferred construction of one embodiment of my invention, I wish it understood thatmy invention is not limited to the embodiment shown and described, but that major changes involving omission, substitution, alteration and re-arrangementof parts and functions may be made without departing from the scope of my invention, which is best defined in the following claims.

Claims:

1. A grinder comprisingV in combination an ab 1asive tool; work rotating means; tool rotating means; traverslng means for trav ersing said tool and the work, one relative to the other; reversing means for said traversing means including two oppositely effective, driving elements, and shifting means providing for alternate engagementv of said driving elements; and feeding means actuated by shifting movement of said shifting means.

2. A grinder comprising in combination an abrasive tool; traversing means for traversing said tool and the work one relative to the other; reversing means for said tra'versingmeans, including two oppositely .effective driving elements and shifting means providing for alternate engagement of said driving elements; `and automatic feeding means, the operation of which is timed by and coincident with the operation of said reversing means.

3. A grinder comprising in combination an abrasive tool; traversing means for tr'aversing said tool and the work, one relative to the other; reversing means for said traversing means,- providing for change of the points of reversal; feeding means; and automatic timing means insuring substantial coincidence of operation of said reversing means and said feedin means when the points of reversal of said reversing means are changed.

4..,A grinder comprising in combination an abrasive tool; traversing means for travcrsin'g said tool and the work, one relative "said feeding means, automatically tothe other; reversing means for said traversing means including tappet means adjustable to change the points of reversal; feeding means; and actuating means for timed by said tappet means to provide substantial coincidence of reversal and feed.

5. An oscillating ball race grinder, comprising in combination a work support; an abrasive tool; automatic means for oscillating said work support to traverse the work relative to the tool, including two oppositely effective driving elements; automatic reversing means providing for alternate engagement of said driving elements; and automatic feeding means actuated by said automatic reversing means and providing for feed of the tool toward the work substantially coincident with the operation of said automatic reversing means.

y6. An oscillating grinder comprising in combination a work support carried by an oscillatory support, a worm gear operatively connected to said oscillatory support, two worms, a shifting cage carrying said forms for alternate engagement with said worm gear, and feed mechanism actuated by shifting movement of said shifting support.

l. a rotating tool spindle; a rotating work spindie; and feed means for shifting one of said spindles relative to the other, includinga ratchet, a pawl for said ratchet,`a cam for imparting ratchet turnin movement to said pawl and manually opera le means for varying the movement imparted to said pawl by said cam.

8. A grinder comprising in combination a rotating tool spindle; a rotating Work spindle; and feed means for shifting one of said spindles relative to the other and including a ratchet 29, a pawl 30, a rod 31, and a'cam 32, having a to and fro movement for imparting movement to said rod 31 and said pawl 30. v

9. A grinder comprising in combination a rotating tool spindle; a rotating work spindle; traversing means for impart-ing traversing movement to the work and tool, one relative to the other; reversing means for said traversing means, including two oppositely effective driving elements, and shifting means 19 carrying saidv driving elements; and feed means for shift-ing oneof said spindles relative to the' other, said feed means including a cam 32, moved to and fro by shifting of said shifting means 19, a rod 31, reciprocated in at least one direction by said cam 32, and ratchet and pawl means actuated by reciprocation of said rod 31.`

10. A grinder comprising in combination work rotating means; tool rotatingmea'ns; and feed means including a ratchet, a pawl,

A grinder comprising in combination meansv for imparting to and fro movement gradually decreasing the extent of to and fro A movement of said pawl as feeding movement progresses.

11. A grinder comprising in combination Work rotating means; tool rotating means; and feed means including a ratchet, a 'pa\vl, a cam for imparting to and fro movement to said pawl and means for automatically gradually decreasing the effective throw of said cam, whereby the to and fro movements of said pawl are automatically gradually de creased in extent as feeding progresses.

12. A grinder comprising in combination work rotating means; tool rotating means; traversing means for traversing the tool and work, one relative to the other; reversing means for said traversing means including two oppositely effective vdriving elements;

-and feeding means actuated by shifting" movement of said shifting meansand having a pawl 41 engaging a ratchet 40, operatively connected to means for reducing the rate of feeding movement as feeding movement progresses.

13. An automatic bally race grinder comprlsmg 1n combinatlon an osclllatory Work support; a frame, a cross feed slide carrled by said frame, a longitudinal slide Carried Vby said cross slide, and a Work spindle carv cross feed slide.

14. A grinder comprising-in combination a rotating work spindle; a rotating tool spindle; land feeding means, including a shifting cam, a coperating spring pressed element, a pawl operatively connected to said i spring pressed element, a ratchet engaging said pawl and means* operatedv by said ratchet for shifting one of said spindles relative vto the other.

In` testimonywhereof, I have signed my name to this specification.

FREDERICK H. HALSTEAD. 

